Arch structure



- P. B. HILL 2,175,292

ARCH STRUCTURE Filed June 14, 1932 v Wow ATTW Patented Oct. 10, 1939UNITED STATES PATENT OFFICE ARCH STRUCTURE Rock, Ark.

Application June 14, 1932, zSerial No. 617,212

6 Claims.

Arch or arch-like structures such as culverts, tunnel linings and wellcurbs, whose curvature is of short radius, and are designed as pipes ofconstant radius and uniform loading, have been made of curved steelplates, but their manufacture is costly because a separate die forpressing them is required for each curved plate radius and that means amultiplicity of dies, and though provided with flanges, as in the caseof liner plates, .0 to impart strength, such flanges cannot be made deepenough to give adequate strength in long spans. With arch structures ofsteel of greater radius and long span, the loading may be and usually iseccentric to the axis and stresses occur that are too great for theseflanged plates, and corrugated plates when corrugations are resorted to,to supply strength. Accordingly, it has been the practice to employarched ribs to supply strength which is lacking in the plates. Thesearch structures of longer radius and great span are exemplified bybridges, roofs, concrete forms with curved surfaces, and the like, andmy invention has for its aim to provide for steel arch structures ofsuch description made up of pressed steel plate units which will havethe important economic advantages coming from a form of unit which willnot require a multiplicity of dies and which will require no arched ribsbut which will have all structural strength in themselves as to requireno arched ribs. To eliminate the need for a multiplicity of dies, myplates are flat and not curved so that the surface of the arch built upis a succession of adjoining flat plate units so assembledas to extendin a curve of the desired radius and which have side Webs of such formand depth as tosupply the requisite strength to render the structureindependent of ribs which are necessary to supply strength that platesthemselves inherently lack.

My invention consists in whatever is described by or is included withinthe terms or scope of the appended claims.

In the drawing:

Fig. 1 is a View partly in side elevation and partly in section of aportion of an arch constructed of pressed steel units in accordance withmy invention;

Fig. 2 is a detail view in perspective of one of the units, such unitbeing of rectangular form;

Fig. 3 is a similar view of another unit embodying my invention, also ofrectangular form;

Fig. 4 is a top plan view of a diamond-shaped unit embodying myinvention;

Fig. 5 is a side elevation thereof;

Fig. 6 is a bottom view thereof;

' Fig. '7 is atop plan view of the blank from Which the unit shown inFigs. 4 to 6 is made;

Fig. 8 is a detail VieW'in horizontal section of the contiguous portionsof four diamond-shaped units assembled;

Fig. 9 is a diagrammatic view of a portion of an arch roof of assembleddiamond-shaped units;

Fig. 10 is a view in vertical section of a portion of an arch roof builtup of fiat flanged pressed steel units and built-up ribs that supportsuch units;

Fig. 11 is a section on the line I I-I I of Fig. 10.

The pressed steel units shown in Figs. 1, 2 and 3 have a rectangularflat plate member I0, which in assembly with similar units provides thearched or curved surface of the structure and which at each of itsopposite sides has a vertical flange II, that constitutes astrength-furnishing web at each side and which is slightly longer thanthe flat plate I0, from end to end, and which unit at each end has anarrow, vertical flange I2, that reaches from side to side of the plateand projects at substantially right angles from the plate Ill, into thespace between the two side webs II. These narrow flanges I2, stiffen theplate I0, and being provided with bolt holes i3, constitute the meansfor fastening together end to end adjoining units, the depth of thestiffening flanges I2, not being sufficient to hinder the curvilineararch formation as shown in Fig. 1 in the direction of the units from endto end.

The supporting webs I I are provided with two sets of holes, one set I4,being adjacent the top and the other set I5, being adjacent the bottomfor bolts to unite side by side adjoining units and the bolt holes I5,are closer together than the holes I4, to enable adjoining units to beplaced with their plates ID, at an angle to one another to suit theradius of the arch. To give additional stifiness to the supporting websII, of the unit at the edge away from the plate Ill, such edge may beprovided, as shown in Fig. 3, with a narrow flange I6, the flangeon oneweb being outturned and the flange on the other web being inturned andsufliciently displaced so that it will clear theoutturned flange of theimmediately adjacent unit. If desired, both flanges E6, of the same unitmay be turned outward and or" another unit turned inward at levels thatwill permit overlapping when the units are placed side by side.

The vertical webs I I, besides taking stresses as structural elements ormembers, also stiffen the plate member.

The diamond shape unit, shown in Figs. 4 to 9, has in plan view'thediamond shape top or arch surface forming plate I00, and at each side avertical flange I I0, these flanges constituting webs which form thestructure supporting elements, as Well as stiffening means and means forbolting adjacent units in the assembled relation shown in Fig. 9,suitable holes being provided in the webs near the upper and lower edgesthereof for bolts, and preferably each web at its free edge has aninturned narrow stiffening flange I60.

The axes passing through the apexes or points of the diamond arepreferably of different length, the shorter axis being transverse of thearch, or parallel with the arch axis, and the webs at each apex on eachof the two axes are divided by slits [1, that reach to the apexes of thesurface-forming plate I00, so that the adjoining ends of the webs whenthey are formed by bending the blank shown in Fig. 7, will lap by oneanother and bring into alinement the bolt holes I8, adjacent the plateI90, and the bolt holes 19, near the opposite edge of the web, andbyshortening the distance betweenthe bolt holes IQ, of the same web bybending the plate I00, on the short axis, the desired curvature of thearch produced by assembled units extending in line with one another onthe long axis, will be produced. As shown in Fig. 8, overlapping webs offour adjacent units are joined by a singlebolt 26, that passes throughregistering holes 18 or l9, as the case may be, in the overlapped webs.The extremities of the webs at the apexes on the long axis are projectedbeyond the apex of the finished blank and those of one unit overlap andinterlock as shown in Fig. 8, with those of an adjacent unit.

To enable variation in the degree of flexing or bending of the unit onits short axis, the bolt holes 18, are or may be elongated lengthwise ofthe web, that is be in the form of slots.

Obviously, to suit special conditions of the arch, half diamond unitsare provided, the line of division being along either the short or thelong axis and in that case the unit will be a triangle whose base is.either the short axis or the long axis. Thus, the triangle whose base isthe short axis may advantageously be used at the arch abutments, or tocreate or frame rectangular openings necessary in the body of the arch;and the triangle whose base is the long axis is advantageously used atthe face of the arch with the base, of course, outermost, and it may beused to provide rectangular openings in the body of the arch. And twosimilar triangular units obviously may be bolted together to form thediamond shape unit. The stifiening flange corresponding to the flange559 in Figs. 4 to 6 need not be employed with the half diamond unitwhere the long axis is the base of the triangle, or in other units wherethe stresses in the webs do not demand.

In arch structures made wholly of the pressed steel units, the webs andflanges may project downward from the flat or top plates, or toward thearch center, or may project upward from the flat or top plates, or awayfrom the arch center, for in either case, the webs act the same and arethe essential supporting elements of the structure. For instance inconcrete structures, the units may be inverted to serve as casting formsfor the concrete and they may be left in place so that the webs andflanges form reinforcement for the concrete, or in roof structures, thespace between the upturned webs and flanges may be filled withinsulating material and covered with roofing material,

Referring to what is shown in Figs. 10 and 11, I employ pressed steelunits which include a long comparatively narrow, rectangular or oblongplate 2|, with downturned flanges 22, at each side and at each end,there being correspondence only in this general respect to the unitsshown in Figs. 1 to 3, but these units are not self-supporting bythemselves when united in an arch and, accordingly, with them, girdersare employed. To the vertical web of these guides at the top the shortends are bolted or riveted and the long side flanges of adjoining unitsare bolted together, these flanges being so shallow as not to interferewith the arch curvature produced by giving a curved upper edge or top tothe supporting girders. These girders are made of pressed steel andinclude a web member 23, and outturned flange 24, at the bottom, made insimilar units of suitable length and bolted or riveted together with thewebs back to back and breaking joints and so that the flanges 24, at thebottom project in opposite directions and lengthwise extend at thenecessary incline to form the arch. This provides an inexpensive andstrong but light structure and one which enables the employment of flattopped cover units in the erection or production of an arched structure.

What I claim is:

1. An arch-forming unit of pressed steel comprising an arch-formingplate that has a flat surface and vertical webs integral therewithextending entirely along side edges of such plate and having dimensionsthat make them the vertical stress-receiving members of the structurecomposed of similar joined units, the vertical side webs extendingbeyond the ends of the flat surface to overlap the vertical webs of anadjacent joined unit.

2. An arch forming unit as in claim 1 in which the plate has on itsedges at right angles to said webs flanges that extend into the space inrear of such extensions and which are narrow compared with the Verticaldimensions of said side webs.

3. A tubular structure composed of a plurality of abutting substantiallydiamond shaped plates, each of said plates having a pair of edges ofuniform length converging to a point and forming one pointed end for theplate, and having two other edges of the same length as the aforesaidedges, said two other edges also converging to a point and forming asecond pointed end for the plate, the points of said ends being disposedin a plane at right angles to the length of the tubular structure, allof said edges being provided throughout their lengths with lateralflanges, and bolts securing the flanges of the various plates together,whereby half the number of said flanges are pitched in one direction andthe others are pitched in the other direction to effectively brace thetubular structure.

4. A tubular structure composed of diamond shaped plates disposed inannular series with the pointed ends of the plates of any seriesdisposed in a single plane at right angles to the axis of the tubularstructure, the plates of any of said annular series being in abuttingrelation with the plates of the adjacent annular series, all of theconverging edges of said plates being of uniform length and providedthroughout their length with lateral flanges, said flanges of eachannular series of plates being bolted to the flanges of the adjacentannular series, whereby half the number of said flanges are pitched inone direction and the other half are pitched in the other direction toeffectively brace the tubular structure.

5. A tubular structure composed of a plurality of side by sidesubstantially diamond shaped plates, each of said plates having a pairof edges of uniform length converging to a point and forming one pointedend for the plate, and having two other edges of the same length as theaforesaid edges, said two other edges also converging to a point andforming a second pointed end for the plate, the points of said ends ofthe plate being disposed in a plane at right angles to the length ofsaid structure, all said edges being provided throughout their lengthwith lateral flanges, and bolts securing the flanges of the variousplates together, whereby half the number of flanges are pitched in onedirection and the other flanges are pitched in the other direction, saidplates being so positioned that any one of said flanges lies throughoutits length alongside substantially the full length of an adjacent flangeof an adjacent plate, whereby half the number of said flanges formreinforcing members pitched in one direction and the other flangesjointly form reinforcing members pitched to the same extent in the otherdirection to effectively brace the structure.

6. A tubular structure composed of diamond shaped plates disposed inannular series with the pointed ends of the plates of any seriesdisposed in a single plane at right angles to the axis of the tubularstructure, the plates of any of said annular series being in side byside relation with the plates of the adjoining annular series, all ofthe converging edges of said plates being of uniform lengths andprovided throughout their lengths with lateral flanges, said flanges ofeach annular series of plates being bolted tothe flanges of adjacentannular plates, whereby half the number of said flanges are pitched inone direction and the other flanges pitched in the other direction, saidplates being so positioned that any one of said flanges lies throughoutits length alongside substantially the full length of an adjacent flangeof an adjacent plate, whereby half the number of said flanges formreinforcing members pitched in one direction and the other flangesjointly form reinforcing members pitched to the same extent in the otherdirection toeffectively brace the structure.

PHILIP B. HILL.

CERTIFICATE OF CORRECTION. Patent No. 2,17 5 292. October 10, 1959.

' PHILIP B. HILL.

It is hereby certified that error appears in the printed specificationof" the above numbered patent requiring correctionas follows: Page 2,sec-- 0nd column, line 10, for the word "guides" read girders; and thatthe said Letters Patent should be read with. this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this lhth day of November, A. D. 1959.

(Seal) ,Henry Van Arsrlale,

Acting Commissioner of Patents.

